App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 731 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) notes to read offline
2. 2.💾 What number does this code show?
   let lives = 6;
   lives = lives - 5;
   lives = lives + 2;
   show(lives);
3. 3.True or false: your last game level fits saving in the cloud. (a) False (b) True
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Kabir", "Arjun", "Aman", "Zoya", "Riya"];
   show(friends[1]); (a) Kabir (b) Aman (c) Zoya (d) Arjun
5. 5.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
6. 6.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 What number does this code show?
   let score = 6;
   score = score - 1;
   score = score + 2;
   show(score);
8. 8.💾 What number does this code show?
   let friends = ["Riya", "Kabir", "Aman", "Zoya"];
   friends.push("Meera");
   show(friends.length);
9. 9.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
10. 10.💾 What number does this code show?
    let notes = ["Sports", "Art", "Hindi"];
    notes.push("Science");
    show(notes.length);
11. 11.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
12. 12.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
13. 13.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 2;
    show(score);
14. 14.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Maths (c) Art (d) Hindi
15. 15.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
16. 16.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 What number does this code show?
    let friends = ["Meera", "Arjun"];
    friends.push("Kabir");
    friends.push("Riya");
    show(friends.length);
18. 18.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Maths"];
    show(notes[1]); (a) Maths (b) Art (c) Sports
19. 19.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
20. 20.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) photos on two devices (d) your last game level
21. 21.Which of these fits saving in the cloud? (a) the sound on/off setting (b) chat messages to friends (c) your last game level (d) notes to read offline
22. 22.💾 Which can hold many values in order? (a) a list (b) a button (c) a switch (d) a single number
23. 23.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a draft you are typing (d) a class leaderboard
24. 24.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
25. 25.💾 What number does this code show?
    let coins = 9;
    coins = coins - 4;
    coins = coins + 4;
    show(coins);
26. 26.💾 What number does this code show?
    let points = 7;
    points = points - 4;
    points = points + 5;
    show(points);
27. 27.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
28. 28.💾 What number does this code show?
    let songs = ["Ocean", "Stars", "Rain", "Monsoon"];
    songs.push("Kites");
    songs.push("Sunrise");
    show(songs.length);
29. 29.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
30. 30.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Science", "Sports", "Maths", "Music"];
    show(notes[0]); (a) Hindi (b) Maths (c) Sports (d) Science
31. 31.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Stars", "Rain", "Ocean"];
    show(songs[3]); (a) Rain (b) Sunrise (c) Stars (d) Monsoon
32. 32.💾 What number does this code show?
    let stars = 8;
    stars = stars - 1;
    stars = stars + 2;
    show(stars);
33. 33.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Kabir", "Zoya"];
    show(friends[0]); (a) Riya (b) Aman (c) Zoya (d) Kabir
34. 34.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
35. 35.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
36. 36.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
37. 37.💾 What number does this code show?
    let notes = ["Maths", "Science"];
    notes.push("Hindi");
    show(notes.length);
38. 38.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) a class leaderboard (d) photos on two devices
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Art (c) Music
40. 40.💾 What number does this code show?
    let songs = ["Stars", "Monsoon", "Sunrise"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);

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